Tropical cyclones over the Mediterranean Sea in climate change simulations

Tropical cyclones form only under specific environmental conditions. Anthropogenic climate change might alter the geographical areas where tropical cyclones can develop. Using an ensemble of regional climate models, we find an increase in the extremes of cyclone intensity over the Mediterranean Sea under a climate change scenario. At least for the most sensitive model, the increase in intensity is clearly associated with the formation of tropical cyclones. Previous studies did not find evidence of changes in the projected areas of formation of tropical cyclones (Intergovernmental Panel on Climate Change, 2007; Walsh, 2004; Lionello et al., 2002). Those studies were based either on relatively low-resolution global climate models or on one particular regional climate model. The use of a multi-model ensemble of relatively high-resolution regional climate models has allowed us to detect for the first time a risk of tropical cyclone development over the Mediterranean Sea under future climate change conditions.